question_answer 24)

Yellow light emitted from a sodium lamp has a wavelength X of 580 nm. Calculate the frequency (v) and wave number \[(\overset{\_\_}{\mathop{v}}\,)\] of the yellow light.

Answer:

Wave number, \[\overset{\_}{\mathop{v}}\,=\frac{1}{\lambda }=\frac{1}{580\times {{10}^{-9}}}\] \[1.724\times {{10}^{6}}{{m}^{-1}}\] Frequency, \[v=\frac{c}{\lambda }=\frac{3\times {{10}^{8}}}{580\times {{10}^{-9}}}\] \[=5.172\times {{10}^{14}}Hz\]